| 引用本文: | 陈晖,刘志兵,王西彬.旋转投影法评定孔类零件轴线直线度误差[J].哈尔滨工业大学学报,2020,52(7):147.DOI:10.11918/201910044 |
| CHEN Hui,LIU Zhibing,WANG Xibin.Evaluation of axis straightness error of hole parts by rotating projection method[J].Journal of Harbin Institute of Technology,2020,52(7):147.DOI:10.11918/201910044 |
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| 摘要: |
| 轴线直线度误差是精密孔类零件的一项重要指标,影响零部件的工作性能、装配精度与使用寿命,为能够精确地计算孔的轴线直线度误差,提出一种旋转投影的误差评定方法. 通过对测量点做齐次坐标变换与旋转投影,使各测量点围绕最小二乘中线旋转到同一平面,将空间问题转化为平面问题；在平面点集中预先选择3个控制点,根据控制点、测量点到控制线距离的关系,不断利用距离比例系数更新控制点,直至3个控制点到控制线的距离的绝对值最大,从而得到轴线直线度误差值,此时3个控制点满足最小区域的“高低高”或“低高低”准则. 本方法无需复杂的非线性优化过程,计算量小,评定结果精度高, 旋转投影保留了测点之间的距离关系,可有效避免直接投影遗漏控制点组合的问题. 计算结果表明:与其他评定方法相比,本方法的评定结果精度更高,耗时在0.1 s以内,能够用于精密制造行业孔类零件的直线度误差评定,具有较高理论与实际应用价值. |
| 关键词: 空间直线度 误差评定 旋转投影 最小二乘法 控制点 |
| DOI：10.11918/201910044 |
| 分类号:TH161.12 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(51375055)； |
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| Evaluation of axis straightness error of hole parts by rotating projection method |
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CHEN Hui1,LIU Zhibing1,2,WANG Xibin1,2
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(1. School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China; 2. Key Laboratory of Fundamental Science for Advanced Machining, Beijing Institute of Technology, Beijing 100081, China)
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| Abstract: |
| To calculate the straightness error of the axis of hole accurately, an error evaluation method based on rotating projection was proposed. According to the homogeneous coordinate transformation and rotating projection, the measuring points are rotated to the same plane around the least square line. The spatial problem was transformed into a plane problem. Three control points were pre-selected in the plane point set. Considering the distance from control points and measurement points to the control line, the control points were continuously updated by using the distance ratio coefficient until the absolute value of the distance between the three control points and the control line was the largest. The three control points met the criteria of "high and low and high" or "low and high and low" in the minimum area. This method does not need complex nonlinear optimization process, and has small calculation amount and high accuracy of evaluation result. Rotating projection preserves the distance relationship between the measuring points, which avoids the problem of missing the control points combination in direct projection. The results show that the method has higher accuracy than other evaluation methods and takes less than 0.1s. |
| Key words: spatial straightness error evaluation rotating projection least square method control point |
